Don't buy from places like Vodafone shop or Orange, as they won't just be locked, but will also have their branding and bloatware on them (Orange is especially bad for this).
I'm not recommending these shops, because I'm not a fan of them either, but Carphone Warehouse, and now Phones 4U sell phones in their original state, with original software on and they aren't locked (The former has never sold locked phones to my knowledge).
You'd need to buy a £10 topup, then it's good to go anywhere. Maybe a UK simcard could be useful over there?
Really though, are phones cheaper in Phils? So I'm going over soon - could I walk into a shopping mall and buy one £20 or more cheaper than in UK?
